Apparatus for twisting metal bars



W. STUBBS.

APPARATUS FOR TWISTING METAL BARS. APPLICATION FILED JUNE 3, 1920.

1 ,395,617. Patented Nov. 1, 1921.

2 SHEETS-SHEET I.

W. STUBBS.

APPARATUS FOR TWISTINGMETAL BARS.

APPLICATION HLED JUNE 3,1920.

Patented Nov. 1, 1921.

2 SHEETSSHEET 2- UNITED STATES PATENT OFFICE.

WILLIAM-STUBBS, 0F SHEFFIELD, ENGLAND.

APPARATUS FOR .TWISTING METAL BARS.

Application filed .Tune 3, 1920.

To all whom it may concern: 7

Be it known that I, WILLIAM STUBBs, a subject of the King of Great Britain and Ireland, residing at Sheflield, in the county of .York, England, have invented new and useful Improved Apparatus for Twisting Metal Bars, of which the. following 1s a specification.

This invention relates to the twisting of metal bars into spiral form (for any purpose for which twisted bars are used, or formaking into drills, angers and the like .tools) as the'said bars issue from-the rolls of a rolling mill, and the invention'consists in an improved method of and means for effecting the above named objects whereby a twisted bar and. any remaining straight portion may be removed from the twisting dies withouthavingto take any; of the die apparatus apart.

The preferred form of .die which I provide according to this invention consists of a number offlat cylindricaldisks each of suitable thickness'and each having a hole formed centrally in it, the opening at one side of which is of the same shape as the bar being rolled and thesides ofthe holeare so beveled and inclined that when the disks are fixed in position against one another, the hole throughthem forms a spiral. The disks are inclosed in a box or cylinder, the front end of which forms a guidefor thebar from the rolls to, the disks. 7

My inventio-n'will be better understood on' reference to the accompanying drawings which aretoward the'rolls). v

Figsj5 6 7*,and 8 are viewsof the reverse faces of the die members shown in Figs; '5 to 8. I

Fig. 9 is a side view of one of the die members.

Fig. 10 is an end view of the dies assem- Specification of Letters Patent.

Patented Nov. 1, 1921.

Serial No. 386,181..

bled and showing in full and dotted lines, the contour of the openings in same.

Fig. 11 is a side elevation of the same.

The same letters refer to similar parts throughout the several views.

Referring to the drawings, a die holder 1 is shown arranged in operative position in proximity to a pair of rolls 2, 3, the front portion of the die'holder being rounded at thetop, in the form shown, 'as' indicated at 4 and the rear'portion being square shaped asshown at 5. At the front end, the die holder 1 is provided with a projecting portion or tray 6 extending in between the rolls 2, 3, and adapted to receive the rolled bar which is required to be twisted as it issues from the rolls. The die holder 1 is formed as a hollowcylinderhaving a uniform bore open at. the rear end andclosed at the front end except that the front end contains an opening 7 to admit the bar to be twisted, this opening being continued as a passage 8 formed in a raised central portion 9 of the projection tray 6 and terminating in a splayed opening or slot 10 in the sloping front end 11 of the tray 6.

An opening or slot 12 is formed in the top of the square portion 5 of the die holder 1 '(Fig. 41) adapted to receive a locking plate 13 having lateral members 13 and 13 which bear against a tubular distance piece 14 which in turn again bears against the flanged end 14 of a tube 14: on the forward face of which are lugs 14 engaging in slots 28 and. 28 in the face of the-rearmost member of a series of die members 15, 16, 17, 18, arranged in the die holder 1.

Four separate and independent die mem bers. are shown in the construction illustrated but it is to be understood that any desired number may be employed as may be considered necessary in order to conveniently impart the desired twist to the bar under treatment. Though not illustrated it will be readily understood that washers can be placed between the die members when desired.

The die'members 15 to 18 as shown in the drawings, are in the form of circular disks or plates adapted to beassembled together in one definite order, namely, in the order in Fig. with the disk 15 arranged at the'rear end and the disk 18at the front end of the said series. This order is determined by in the configuration of the front and rear.

the formation of the central hole provided in each of the said disks and which has to be traversed by the bar to be twisted.

Reference to Fig. 10 will show how the respective openings in the dies are arranged in relation to each other, when set for the purpose of twisting a bar. The outlines shown on the figure are those on the rear or delivery sides of the respective disks and the longitudinal center lines 1-1, 22, 3-3, 4 1- indicate the several angles of inclination through which the bar is twisted in its progress through the dies. As will be hereafter more fully explained, the bar is caused to assume the different angles of inclination between the delivery opening in one die and the delivery opening in the next, by means of beveled and inclined faces leadingfrom one to the other.

Referring to Fig. 5 it will be seen that the front disk or die member 18 is provided with a central elongated opening 20 adapted to receive a fiat bar to be twisted having a considerable width relatively to its thickness, this opening 20 being slightly inclined to the horizontal. The front edge 21 of the hole 20 first encountered by the bar coming from the rolls 2 and 3 is beveled or sloped in such a manner that, while the bar encounters a substantially horizontal edge of the hole in question, by the time the bar is issuing from the hole 20 at the rear side of the member 18. it is given a twist to the right to the extent shown in Fig. 5 and as indicated by the center line 1-1 (Fig. 10). Thenext die member which the bar has to pass through is that shown at 17 in Fig. 6, in whichit will be seen that the lower left hand corner and the upper'right hand corner are'cut away at 22 to permit of the entrance of the bar from disk 18, and inclined faces so formed in the disk 17 lead the bar through the opening 23 in the rear face .where it assumes the inclination indicated by the center 2-2 (Fig. 10). In like manner the con figuration of the opening 24: in the front face of disk 16 (as shown in vFig. 7) enables the bar to pass from disk 17 and be guided through the back opening 25 in disk 16 (see Fig.7) when it will have the inclination indicated by the center line 33 (Fig. 10). The same principle of construction is adopted openings 26 and 27 in disk 15, and as the bar emergesfrom the opening 27 in the rear face, it assumes the inclination indicated by th center line 4=-4; (Fig. 10).

- By the time any given length of the barhas passed through the series of disks and. has finally issued from the back edges of the hole 27 of the rearmost disk 15, the said length of barwill have received a twist to the right through about an angle of.135.

In order to assemble or pack the disks 15, 16, 17, 18t0gether in a compact or snug manner, the disk 15 is provided on its front face with pins 28 and 28 adapted to be inserted in circumferential slots 29 and 29 formed in the adjacent disk 16, while the disk 16 is provided in a similar manner with pins 30 and 30 adapted to be inserted in circumferential-slots 31 and 31 formed in the adjacent disk 17; finally the disk 17 is provided on its front face with pins 32 and 32 adapted to be insertedin circumferential slots 33 and 33 formed in the foremost disk 18. t

In addition to the above pins and slots, the foremost disk 8 has pins 34: and 34 'on its front side which fit into holes 35 and 35 formed in the end wall of the die holder. A keyway 36 is formed in each of the die disks 15, 16, 17 18 and when the said disks are correctly assembled together in position to carry out a twisting operation, they are engaged by a key 37 hinged in any suitable manner to the die holder and passing through a longitudinal slot 38 formed in the top of the die holderl, and thus firmly hold the die holder 1, and thence through the twisting die consisting ofthe separate die 1 members 18 to '15 whence thebar passes" intothe tubular guide ltand so to the exterior of the apparatus. i

It will be understood rolls, the entire lengthof the bar 'can notbe twisted since there is no power to push the last portion through the twisting dies, and

also the bar can not be readily pulledv that when the end of a bar being rolled has passed out of the through the dies by hand when in their set position. At this stage of the operation, the key 37 is removed from the slotsfin the die members, and the bar is then pulled to draw the plain portion through the dies,

which can now be doneinasmuc'h as the dies yield and permit of partial rotation (due to the endwise pull on the bar) until all the longitudinal die openings are in the "same horizontal plane (which will readily be understood on reference to Fig. 10) .and consequently a clear passage is provided for the plain portion of thebar.

When it is desired to reset the die members into positionfor twisting, the handle 14 on the guide 14 is given the'necessary turning movement to enable the flange 14: through the medium of the pins 1 1 to turn the die member 15 until the pins 28 and 28 I on its forward face traverse the length of the slots 29 and 29 in the adjacent member 16which is then moved in like manner and SO i t rn are the Whole series until further movement is impossible, when the longitudinal axes of the die openings will have assumed the respective angles of inclination shown in Fig. 10, and all the keyways will be in line ready to receive the key 37.

Having now described my invention what I claimand desire to secure by Letters Patent is An apparatus for twisting metal bars into spiral form, comprising a base, forming adie holder, a tubular guide at one end of said holder, a tray provided with a passage at the other end of the holder for receiving the bar to be twisted, a plurality of fiat cylindrical disks disposed within the holder, each of said disks having a helical slot dis posed centrally thereof, said slots forming a continuous helix, means for locking the disks against rotation, and means for partially rotating said disks.

In testimony whereof I have signed my name to this specification.

WILLIAM STUBBS. 

